3V0415.01 Functional classification: two examples, one in error (3/13/79)

Peggy has begun to classify objects by what she knows their use to be.
Some examples are equivocal, though I remain convinced of their
interpretation. For example, Peggy has been “brushing” her hair. This
could be from having her hair brushed, from seeing Miriam brush her
hair, or it could be her use of the object according to a functional
definition of what it is for. A further complication, with a hair brush, is
that Peggy passes so many things behind her neck, it is hard to be
certain that she is really “brushing.” (The best evidence is that she
repeatedly brushes her hair even if she eventually passes the brush
behind her neck.)

There is less certainty about the second example, depending as it does
on an incorrect assimilation, Peggy hates to have her nails cut. She
carries on terribly. She sat in my lap demanding objects from my table.
One of the first that came to her hand was a pair of tweezers. Peggy
held one end and touched the other to each of the toes on one foot in
succession. (The day before, she had had her nails clipped.) I infer
that Peggy saw the tweezers as a nail clipper (both are of the same
length and have a small set of jaws at the end). The functional
classification it witnessed by her application of the tweezers.